Effects of patient load and travel distance on HIV transmission in rural China: Implications for treatment as prevention

BACKGROUND: Sustained viral suppression through ART reduces sexual HIV transmission risk, but may require routine access to reliable and effective medical care which may be difficult to obtain in resource constrained areas. We investigated the roles of patient load and travel distance to HIV care clinic on transmission risk in HIV serodiscordant couples in Henan Province, China. METHODS: Cox proportional hazard models were used to compare HIV transmission events across couples living near, medium, or farther distances from their assigned HIV care clinics, as well as those attending clinics where clinicians bore high versus low patient loads. RESULTS: Most (84·4%) of the 3695 serodiscordant couples lived within 10 kilometers of their assigned HIV clinic, and most (73·5%) attended clinics with patient-to-provider ratios of at least 100:1. In adjusted Cox models, attending clinics where clinicians bore average patient loads of 100 or more elevated HIV transmission risk (aHR, 1·50, 95% CI, 1·00–4·84), an effect amplified in village tier clinics (aHR = 1·55; 95% CI, 1·23–6·78). Travel distance was associated with HIV transmission only after stratification; traveling medium distances to village clinics (5-10km) increased transmission risk (aHR = 1·83, 95% CI, 1·04–3·21) whereas traveling longer distances to township or county level clinics lowered transmission risk (aHR = 0·10, 95% CI, 0·01–0·75). CONCLUSION: Higher patient loads at HIV clinics was associated with risk of HIV transmission in our population, particularly at village level clinics. Farther travel distance had divergent effects based on clinic tier, suggesting unique mechanisms operating across levels of resource availability. The resource intensity of long-term HIV treatment may place significant strains on small rural clinics, for which investments in additional support staff or time-saving tools such as point-of-care laboratory testing may bring about impactful change in treatment outcomes.